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ultraviolet astronomy

(Encyclopedia)ultraviolet astronomy, study of celestial objects by means of the ultraviolet radiation they emit, in the wavelength range from about 90 to about 350 nanometers. Ultraviolet (UV) line spectrum measure...

Linus, in Greek mythology

(Encyclopedia)Linus, in Greek mythology. 1 Son of Apollo and Psamathe of Argos. He was deserted by his mother on a hillside and devoured by dogs. When Psamathe's father learned what his daughter had done, he had he...

neutrino astronomy

(Encyclopedia)neutrino astronomy, study of stars by means of their emission of neutrinos, fundamental particles that result from nuclear reactions and are emitted by stars along with light. Approximately 100 billio...

X-ray astronomy

(Encyclopedia)X-ray astronomy, study of celestial objects by means of the X rays they emit, in the wavelength range from 0.01 to 10 nanometers. X-ray astronomy dates to 1949 with the discovery that the sun emits X ...

earth, in geology and astronomy

(Encyclopedia)CE5 A. Cross section of the earth, showing its shells B. Detailed cross section of the crust and upper mantle: The lithosphere consists of the hard rock in the crust and upper mantle, lying above t...

National Radio Astronomy Observatory

(Encyclopedia)National Radio Astronomy Observatory (NRAO), federal observatory for radio astronomy, founded in 1956 and operated under contract with the National Science Foundation by Associated Universities, Inc.,...

hero, in Greek religion

(Encyclopedia)hero, in Greek religion, famous person, who after his death, was worshiped as quasi-divine. The heroes might be actual great men and women, real or imaginary ancestors, or “faded” gods and goddess...

Hydra, in Greek mythology

(Encyclopedia)Hydra, in Greek mythology, many-headed water serpent; offspring of Typhon and Echidna. When one of its heads was cut off, two new heads appeared. The second labor of Hercules was to kill the monster. ...

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